Quick acting c-clamp



Nov. 12, 1957 c. L. HUTSON 2,812,789

' QUICK ACTING c-cLAMP- Filed Dec. 20, 1954 6 26 14 J8 m 25 mlllllll'i'u' M "mama?" 27 2s m 56 g 38 .156 1 4 J5 IN VEN TOR.

64 Fa/e0 1. H0750 Arra/e/wm United States Patent an r:

2,,s12 ,7sg QUICK CTI G Clifford L. Hutson, Glendale, Calif, Application December 20', 476,112 b i 3 Claims. o 144- 3 i This invention relates to clamping devices of the oclamp type. i

It is an object of this invention to provide an improved clamping device of this character in which a clamping jaw may be quickly brought into engagement with the wgrk with a free-sliding movement and thereafter tightly clamped responsive to a short screw threaded adjustment thereof. i

It is another object of this invention to provide a clamping device such as described, wherein the work may be quickly released and the work clamping jaw qnickly retracted with a free sliding movement. A further object hereof is the provision of a clamping device such as described which, in one size, is and easily adaptable for holding work over a wide range of sizes.

It is an additional object hereof to provide improved C-clamp embodying the above noted advantageous features.

Another object hereof is the provision of a clamping device of the character describedwhi'ch includes a'no vel means for holding the movable work clamping jaw agairist movement in a direction away from the work'following the free sliding movement of this jaw against the work; whereby the screw threaded tightening means may be effie ctively operated to clamp the jaw against "the" work.

i A further object hereof is the provision in a ela mp such as described, of a novel means for releasing the rneans which holds the movable work-clamping jaw against movement in a direction away from thework.

A further object hereof is the provision ina clamp, ot the character described, of a novel arrangemento f he releasing means and the means by which both the slid g and screw threaded adjustments are'efiected, this a ran e rnent providing for operationofthe releasing means with the fingers of the hand which holds the meanstor 'ctiiig the aforesaid movements of thejaw. f

' This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of one embodiment of theiriveritiori'. For this purpose there is showna forminthe drawings accompanying and forming part of the present specifies mm; This form will now be described in deta'il, illustra t;

ing the general principles of the inveiitionfbutit to understood that this detailed description notto taken in a limiting sense, since the scope oi invention is best defined by the appended claims. '7

Referring to the drawings 1 is a side elevation partly in section of a clamping device embodying the present invention, showing the jaws clamping work therebetween;

Fig. 2 is an enlarged sectional view taken on the line 2-2 o f Fig. l; i i Rig. 3 is asectional viewrtaken on the plane of line 3-3ofFig. 2;

Fig. 4 is a sectional view taken on the plane of line 4-4 of."Fig. 1, showing the releasing means i 2. the pawls are operative to engage the ratchet tss h; d r

.F s- 5 s a V w shrr izo dinaw Fig 4 showing t e releasing ms nsin t e p si n f h i g the pawls out Q' hs seih twith the r tc t. th-

' 'As qwh th asssm h r w a h present vention is embodied'in a c-clamp, but it; is to "be understqq l th t he inv h sn hs h f mh in other forms of clamps or similar devices wherein'it is desired to"pro yide for movement ot a clamping jaw as here shown;

flhs -s jshinss'mpr ss a Q- h P frame 1 formed of a msih r ,4 nd ppqssd ms 1 il t pp sail thsteqh P ts a'hl t pa between h arms 1 s id s is s ssh dsrah s w t n d p h whereby work Qt Ysritms sizs 'm y b sl mns h t one d v as wi he shpa ht as t s s r pt progresses On the enter end of the arm 1b is a stationary or fixed work clamping jaw 2 such as usually provided in G-clamps. The jaw 2 is adapted to cooperate with a movable jaw 3" for dam n work t ss st w in F between h two iawsih' s mahhr which w he hereinafter d i In accordance with thisinvention it is desired to provide tor'a tree sliding movement of the movable jaw 3 into and outof work-engaging position without necessitating the screw threaded-adjustment usually required ind-clamps and similar devices. In other words; it is hased t th u tth m vab ja 3 q k y g t the words and'to'as" quickly retract -it. It is also desired that npen movement of the jaw into work engaging position it will be held against retrograde movement whereby'the desi edrfinal tightening and clamping of the jaw may be etfrjectedwit'h but a shortjs crew threaded axial adjustment thereef; These provisions make it possible for a C-clamp, or similar device of one given size; to be used effectively for clamping work over a wide range of sizes.

Itis also desired to provide fora quick release of the means which'holds the movable jaw against movement in a digectiqn away from the workand to do this with the fingers oi; the hand grasping the means by which'the sliding as ss sw threade ustm a e fi The rneans provided in accordance with this invention, whereb th af rem nt on d desirable pe s of the jaw 3 may be effected; will now be described.

shown in the drawing, the jaw 3 is mounted on one end of a rod'4 extending through a sleeve 5 slidably supported in a tubular bearing member 6 integral withthe outer end of the arm 10. A knurled handle 7 is fixed on the other end of the rod 4 and provides for sliding the sleeve 5 and the rod axially whereby the jaw 3 maybe quickly moved into and out of work-engaging position; 'Ihe jaw 3; acts as a stop to limit the retroaction movement gfthesleevesw. t h l vIhe rod 4 adjacent the end thereof on which the jaw 3 is mounted, isprovided with screw threads Sengaged with a screw threaded portion 2 of the bore through the sleeve 5,: Thus; up'on appropriate turning the handle 7 and thefrod, the latter ismovable axially relative to the sleeve 5 for tightening the jaw 3 against the work. The sleeve 5'is heIdJagain'st turning about itsaxis by means of a key 11 fixed in bore of the bearing'member 15 so as to engage in a keyway 12 extending along the exterior of the sleeve. i a

Means are provided for releasably holding the sleeve 5 and rod {against movement ina directionawayfroin the work; whereby the jaw3may" be'tightened and re leased upon turning the handle 7 and rod 4 relative to the sleeve 5, this being the screw "threaded" adjustment nf the jaw. Accordingly,'the sleeve '5 is provided with re het teeth 1f! along opposite sides thereofadapted to h s a y a thirst srihs-lo s p l lsmouritsd o' the h M U The ratchet teeth 14 are pr o-' h s 1 sas am? h uls 15. ha similar surfaces which abut the square faces of the teeth, whereby the sleeve will be positively held against movement in a direction away from the work.

As the pawls 15 are required to hold the sleeve 5 against retrograde movement incident to the tightening of the jaw by the screw threaded adjustment of the rod 4, a considerable load is imposed on the pawls. Accordingly, the pawls are mounted to resist this load. One way, as here shown, to so mountthe pawls 15, is to provide them with shoulder portions 15a for abutting shoulder portions 6a on the bearing member 6 whereby the load is taken by the member 6.

The two pawls 15, as here shown, may be mounted to rock in longiudtinal grooves 16 in the bearing member 6 each pawl having a depending fulcrum portion 15b intermediate its ends which rocks in a depression 16a formed in the bottom of the associated groove 16. The depth of the grooves 16 is such that the pawls are substantially enclosed therein, with but a portion thereof extending radially from the periphery of the bearing member 6.

The means for spring-loading the pawls 15 as here shown comprises a split and flat spring ring 18 which embraces the pawls and has its ends seated against the flanges 19 on the arm beneath the bearing member 6. The bearing member 6 is provided with a circumferential groove 20 in which the spring ring is mounted so as to urge the pawls against the teeth 14. The pawls may also be provided with transverse grooves 21 in which the spring ring is engaged. As the spring ring 18 is flat in cross section and seated in the grooves and 21, it assists in holding the pawls against axial displacement as well as holds the pawls assembled on the bearing member 6 subject to rocking movement in the grooves 16. This spring ring is installed in the manner of a snap ring and is provided with apertured ends 18a to facilitate the mounting and removal thereof with a suitable instrument not shown.

Means are provided for releasably holding the pawls 15 in engagement with the ratchet teeth 14 as well as disengaged from the ratched teeth. This means as hereinbefore stated is disposed so that it may be operated by fingers of one hand of the operator while this hand grasps the handle 7, thereby facilitating the clamping and releasing of the jaw 3. This means as here shown, includes a cam ring 23 rotatably mounted on the outer end of the bearing member 6 with its inner side face abutting a shoulder 24 on the bearing member. A fiat snap ring 25 seated in a groove 26 in the bearing member 6 abuts the outer side face of the cam ring 23, thereby holding the cam ring 23 against axial displacement from the bearing member 6 while permitting free turning movement thereof relative to the bearing member.

As shown in Figs. 4 and 5, cam surfaces 23a are formed in arcuate recesses 23b in the inner side face of the cam ring 23. These recesses and cam surfaces are angularly spaced about the axis of the ring so that upon appropriate turning of the ring, the cam surfaces will engage the end portions 150 of the pawls 15 and rock the pawls about the fulcrums 15b to disengage the pawls from the ratchet teeth 14.

The ends 15c of pawls 15 will abut the end walls of the recesses 23b to limit the turning movement of the cam ring 23 to the position (see Fig. 4) releasing the pawls for engageemnt with the ratchet teeth 14 as well as the position (see Fig. 5) for holding the pawls out of engagement with the ratchet teeth. The cam surfaces 23a are so formed that the recesses 23b have narrow end portions and wide end portions as will be seen with reference to Figs. 4 and 5. When the cam ring 23 is inposition for disengaging the pawls 15 from the teeth 14, the ends 15c of the pawls are disposed in the narrow ends of the recesses, as shown in Fig. 5, thereby'holding the 'pawlsdisengaged against the action of the spring ring 18.- When the cam ring is in the position shown in Fig. 4, the ends of the pawls 15 are in the wider ends of the recesses 23b.

In all positions, the cam ring 23 acts as a stop to pre vent axial displacement of the pawls 15, as the outer ends of the pawls are disposed in such close proximity to the bottoms of the recesses 23b in the ring, that any slight movement of the pawls move in a direction away from work will be checked by the cam ring.

Appropriate turning movement of the camring 23 is afforded by means of a handle 27 which extends from the ring so as to be disposed on the right side of the frame arm 1c whereby it may be actuated by fingers of the hand holding the knurled handle 7. This handle normally lies for the most part along the arm 10, only the finger piece 28 on the free end thereof projecting out wardly from this arm. I

It should be noted that the pawl and ratchet arrangement assures that the jaw 3 quickly and easily may be moved against the work and will be held against retrograde movement from any position into which it is intentionally moved toward or against the work, whereby the rod 4 may be turned to effect the screw threaded adjustment of the jaw 3 into tight clamping engagement with the work.

Also it is important to note that when it is desired to release the jaw 3 and retract it quickly, the operator without releasing his hand from the knurled handle 7, may with fingers of this hand readily reach the cam ring handle 27 and turn the cam ring 23 so as to disengage the pawls 15 from the teeth 14. As readily the cam ring may be actuated to allow the pawls to engage the teeth 14.

I claim:

1. In a clamp, a frame; a bearing on said frame; a sleeve axially adjustably supported by said bearing; a rod extending through said sleeve and threadedly engaged therewith for axial adjustment relative thereto; a workengaging jaw on said rod; ratchet teeth on said sleeve; said bearing having grooves extending axially thereof; pawls mounted in said grooves with corresponding ends thereof disposed for movement into and out of engagement with said teeth; said teeth and said pawls preventing movement of said sleeve in a direction away from the work; each of said pawls having a fulcrum portion seated on the bottom of the associated groove; said bearing having a groove therein intersecting said axially extending grooves; a split spring ring mounted in said intersecting groove in surrounding relation to said pawls and said bearing to hold said pawls in said groove subject to rocking movement on said fulcrum portions; said pawls having grooves therein in which said spring ring is engaged; said grooves in said pawls being located between said corresponding ends and said fulcrum portions; a cam ring mounted to rotate on and around said bearing in engagement with said pawls; and cam elements on said cam ring engaged with said pawls and operable for rocking said pawls out of engagement with said teeth upon rotation of said cam ring.

2. In a clamp, a frame; a bearing on said frame; a sleeve slidable on said bearing; a rod carried by said sleeve; a work-engaging jaw on said rod; ratchet teeth on said sleeve; said bearing having a slot exteriorly thereof; a pawl in said slot; said pawl having a fulcrum portion between its ends engaged with the bottom of said slot to provide for rocking of the pawl to move one end of the pawl into and from engagement with said teeth; a split ring spring held in embracing relation with said bearing by the inherent resiliency thereof; said spring ring being engaged with said pawl at a point between said one end of the pawl and said fulcrum portion to hold said pawl in said slot and urge said one end of the pawl against said teeth; and cam means mounted on said bearing in engagement with the other end of said pawl and operable to move said pawl out of engagement with said teeth.

3. In a clamp, a frame; a bearing on said frame; a sleeve slidable on said bearing; a rod carried by said sleeve; a work-engaging jaw on said rod; ratchet teeth on said sleeve; said bearing having slots exteriorly thereof; pawls in said slots; said pawls having fulcrum portions between their ends engaged with the bottoms of said slots to provide for rocking of the pawls to move corresponding ends of the pawl into and from engagement with said teeth; said ends of said pawls being extended beyond one end of said bearing; said end of said bearing having shoulders thereon engageable by said pawls when said pawls are engaged with said teeth; said bearing having a groove extending circumferentially of the exterior thereof; a split spring ring mounted in said circumferentially extending groove so as to overlie said pawls and hold them in said grooves; said pawls having transverse grooves therein between said fulcrum portions and said corresponding ends of the pawls; said spring ring being mounted in said transverse grooves; and a cam ring mounted on the other end of said bearing for r0- tative movement; said cam ring having cam portions which embrace the other ends of said pawls and are operable to rock the pawls for moving the pawls out of engagement with said teeth.

References Cited in the file of this patent UNITED STATES PATENTS 243,978 Rorninger July 5, 1881 669,904 Sibert Mar. 12, 1901 768,761 Larson Aug. 30, 1904 786,788 Hudson Apr. 4, 1905 1,357,935 Argetsinger Nov. 9, 1920 1,429,050 Sylvester Sept. 12, 1922 1,445,344 Moltrup Feb. 13, 1923 1,749,491 Kokay Mar. 4, 1930 2,405,018 Crowley July 30, 1946 2,408,801 Miller Oct. 8, 1946 FOREIGN PATENTS 615,047, Great Britain Dec. 31, 1948 

